Study: Air pollution is common cause of heart attacks

Because it affects everyone, air pollution triggers about the same number of heart attacks as individual risk factors such as physical exertion, alcohol and coffee, a new study concludes.

Belgian researchers, after examining three dozen studies to compare triggers, found that cocaine increased the risk of heart attacks the most -- 23 times, while alcohol increased it three times and coffee 1.5 times. In comparison, air pollution increased it just 5%.

Yet when they calculated the population-attributable fraction (PAF) of each, meaning the proportion of total heart attacks estimated to have been caused by each trigger, air pollution came out comparable to better-known risk factors.

"We knew air pollution was a risk factor for myocardial infarction ... but some people think this is just a trivial factor," said the study's lead author Tim S. Nawrot of Hasselt University's Centre for Environmental Sciences in Diepenbeek, Belgium.

Nawrot tells Green House that 5% to 7% of heart attacks could be avoided or delayed if air pollution were eliminated. He advises people at risk for heart disease to avoid strenuous physical exercise in heavy traffic or other polluted areas.

To report corrections and clarifications, contact Standards Editor Brent Jones. For publication consideration in the newspaper, send comments to letters@usatoday.com. Include name, phone number, city and state for verification. To view our corrections, go to corrections.usatoday.com.

About Wendy Koch

Wendy Koch has been a reporter and editor at USA TODAY since 1998, covering politics and social issues. She's begun a quest to build the most eco-friendly home her budget allows. She'll share her experience and give you tips for greening your home. More about Wendy